Air-filter.



F. W. R. WILLIAMS.

AIR FILTER.

APPLICATION FILED MAR..14. 1911.

l. Patented oet. 1918.

4 SHEETS-SHEET l.

:s h Il FI i/'9 1 F. W. H. WILLIAMS.

AIR FILTER.

APmlcATIoN man MAR. x4. |917.

VAPatented Oct. 22, 1918.

4 SHEETS-SHEET 2.

F. W. R. WILLIAMS.

AIR FILTER.

APPLICATION FILED MAII.I4,*I9I1.

Patented Oct. 22, 1918.

4 SHEETS-SHEET 3.

F. w. II. WILLIAMS.

AIR FILTER.

APPLICATION FILED IvIAII. I4, IsII.

Patented Oct. 22, 1918.

WAM

FREIDERCK WILLIAM ROGERS WILLIAMS, F LONDON, ENG-LAND.

AIR-FILTER.

Specication of Letters latent.

Patented (bet. 22, idi.

Application led March 14, 1.917. Serial No; 154,809.

' Great Britain, and a resident of London,

England, have invented certain new and useful Improvements in and Connected with `Itlrir-.Tiltera of which the ollowing is al speciication.

This invention relates to improvements `in and connected with air iilters and has reference to air lilters of that character where the dust laden air is filtered by means of suitably suspended i'ilter bags. The present invention has reference particularly to shaking mechanism, by lmeans of which the bags are cleaned from time to time; of that character where the bags are normally held in tension under the influence of a spring, or' springs, and periodically the upper ends oi' each series ci bags are depressed against the influencent a spring, and are then suddenly released again, so that the spring operates rapidly to extend them into tension again and thus impart a jerk to effect the shaking operation. lThis operation takes place at predetermined intervals, the number ci shakes required and provided for, depending upon the material being dealt with.

it will be understood by those conversant with this type of apparatus that the operations of the lter are continuous because the filtering surfaces e. the bags, are made in groups, and when one group or bags is being subjected to the shaking operation the others are operating to filter and. collectv the dust, a valve controlling the opening of the lter chambers to suction during the filtering period and to atmosphere during the shaking period being operated in synchronism with the throwing of the shaking mechanism out of and into operation. A

The present invention consists of a particular construction and arrangement of mechanism of the foregoing general type, and this construction and arrangement involves as its essential characteristics a slidable valve operating rod carrying a shaking trigger, and means whereby Lthe valve operating rod is caused to moveperiodically, and rapidly operate, a valve to open the filter chamber to suction during the iltering period, and te atmosphere during the shaking period, and at the same time tofcarfry the shaking trigger out of and into a position where it is operated by a rotary shaking cam. Further features oi' importance,

for use in combination with the foregoing essentials, which may b e mentioned specilically are the provision of a timing cam mounted upon one shaft for controlling the periods of operation and a shaking cam mounted upon another shaft for effecting the shaking operation and theprovision on the same shaft of a cam for `raising the valve rod and a cam for .controlling the duration of the shaking and filtering periods While upon another shaft both the cam for moving the valve rod and the cam for effecting the shaking are mounted.

In the accompanying drawings l have illustrated a filter constructed and operated in accordance with my invention.

ln these drawings, 1

Figure 1v is a part sectional front elevation. i

Fig. 2 is a side elevational view of Fig, l.

Fig. 3 is a plan view of Fig. 2.

Fig. i is a sectional elevation on an enlarged scale of the valve operating'mechanism, and

Fig. 5 is a plan view of Fig. si.

Referring to these drawings' the numeral Vl designates avr dust collecting hopper which is common to all the filter bags, and the dust collected in this hopper is removed by a rotating screw conveyer 2 driven by means of pulleys 3, or other suitable gearing, or by any other suitable means. The inlet pipe el for admitting the dust laden air to the filter is connected to the hopper at any convenient position such for instance as that shown in Fig. 2, and above the hopper the ltering chambers or casings 5 are located, and may be provided with doors 9 at top and bottom to permitot1 ready access to the interiorsin the present example two chambers are illustrated, which form a single unit, but it will be understood that any desirable number of units may be provided. Separating the chambers or casings 5 from the hopper l a base plate 6 is provided, and the filter bags .7 are suspended above openings Sprovided in this base plate, the bags being so connected to the base plate that the dust laden air enters the bags, the air passes through the filtering material of the bags,

the dust being deposited on the inside of drawings.

13 and stirrup belt 14, or other` suitable means. The spiders 12 are connected to shaking rods or lspindles 15 which pass up through openings provided in a top plate 16 which closes the filter chambers or casings 5, suitable guides 18 being provided. The topsl of the shaking rods 15 are provided `with caps 17, and compression springs 19 toms are open to a suction fan, or fans, or

the like, andit will be' seen that with the valve 21 in the position shown,in Fig. 2 the lter chamber or casing 5 is open to suction and closed to atmosphere which isthe normal operating position. A shaking and valve control gear is provided for each series of lter bags and these gears are mounted upon the top plate 16. These gears are controlled from a common continuously driven shaking cam shaft 22 which may be drivenv at the desired speed in any suitable manner such` -for'instance, as by a pulley drive as indicated in the drawings.

As the shaking them.

' Referring particularly to Figs. 2, 4 and 5 it will seen that the valve 21 is connected by means lof a link 24 to one end 25 .of a bell crank lever pivoted at 27 to a bracket mounted upon the top plate 16, and the other end 26 of this'bell crank lever is connected -to the extremity of a valveoperating rod 28. Thisvalve operating rod 28 is slidable bodily, and its movement is timed by the timing cams 29 and 46, which are mounted upon a shaft 30, which is driven from the shaft 22 through bevel wheel gearing 31 and a worm drive 32.

This valve operating rod 28 has a dependingdog, or projection 33 which coperates with the timing cam 29, and a depending cam surface orprojection47, having its working surface in thesame horizontal plane as that of the dog 33, which coperates with a cam .146;` and it will be seen that the position shown in Fig. 4 is that where the dog v33 has just fallen olf the highest part of the cam 29 and the projection 47 is on that point of the 'cam 46 where its curvature departs from the circular and this porv tion corresponds to the end of the filtering period and the commencement of the shaking period.- At thsppoint the dog or proand valve control gears I are identical it will suffice to describe one of jection 34 of a cam 35 attached t0 the shaking shaft 22 engages the depending end 36 of the valve operating rod 28, and 'the rod 28 is moved bodily to the right, and this movement causes the reversal of the valve 21 through the bell crank lever 25, 26, and

connecting link 24. This sudden reversal of the valve inconsequence of the partial vacuum existing in the filter casing, effects a reversal of current. By this movement the valve operating rod 28 carries the shaking trigger 37-which is mounted upon a spindle 40 which passes through a vertical slot 4l in the valve operating arm 28 and a horizontal slot 412L in the top parts of the brackets 42a-into position where its arm 38 is in the path of a cam do 39l upon a cam 43 similar y to the cam 35. hen the valve operating rod 28 has reached its extreme position, a catch 44 upon its underside will have depressed a spring stop 45 and become engaged with this stop, so that the rod 28 is prevented from returning. lt will be noticed that in this position the dog 33 will be out ofengagement with the cam 29 and the left hand tip of the projection 47 will engage that part` of the cam 46 where its curvature commences to depart from the circular. Th arm 38 of shakinghtrigger 37 being in the path of the cam -dog 39, every revolution of the shaft 22` will cause the trigger 37 to operate,.and its arm 38*l willL cause the depression of the rod 15 againstl the iniiuence of the spring 19, and immediately the cam dog passes clear, the trigger will be suddenly released and the spring 19 will expand again and impart a jerk which will .insure the shaking of the filter bags. operation willoccur asv often as necessary and is determined by the relative speeds of vthe driving shafts 22 and 30.

This shaking v During these lshaking operations the lifting or releasing cam 46 coperates with the left hand end of the projection or lump 47 on the Valve operating rod 28. This lifting cam 46 comes into operation immediately the valve operating rod 28 has reached its extreme right hand position, and begins to raise the rod 28 slowly; and the camis so shaped that by the time the shaking operation has been effected the'rod 28 will. be raised to its maximum yertical height, and

-the catch 44 on the rod 28 raised clear of the stop 45, whereupon the tension spring 48 will restore the valve operating rod 28 and the valve 21 to normal position, the projection 47 meanwhile sliding over the cam- 46 end. lThe projection or dog 33 on the valve operating rod 28 will now ride upon the high part of the timing cam 29 and the cam 46 is si) shaped that .the projection 47 will .be maintained clear of it whilev the' filtering operation is proceeding2 the dog 33 will then fall ofi:l the cam 29 again to the lower level,

' until it. engages the cam with its right lhand as shown in the drawings and the projection 47 engage the cam 4:6, when the shaking operation will be repeated in the manner before described.

It will be understood -that the purified air will` pass through the filter bags into the filter chamber or casing, and the dust ar rested upon the inner surfaces of the bags will be shaken down into the hopper and removed by the conveyer 2, or by gravity'.

What I claim and desire -to secure by Letters Patent is .1. An air filter comprising a dust collectl ing hopper, a filtering chamber mounted upon said hopper, an inlet pipe for the admission of dust laden air into said chamber,

' said valve-operating rod, means for causing lsaid valve operating rod to slide bodily to operate said lvalve, a shaking trigger and means for momentarily operating said shaking trigger to collapse the filter bags against the influence of the springs andA timing cams for timing` said operations, substantially as specified.

2. An air filter comprising a dust collecting hopper, a filtering chamber mounted on said hopper, filter bags suspended in said filtering chamber, a spider from the arms of which said filter bags are suspended, a spring normally maintaining said filter bags 1n tension, a suction chamber communicating with said filtering chamber, a Valve" for alternately opening saidv filteringV chamber to suction and atmosphere, a valve operating rod, a. link connection between said valve operating rod and said valve,l a shak ing trigger adapted to be intermittently operated to collapse said filtering bags against the infiuencc of the tensioning spring, a shaking cam controlling the operations of -said trigger, a continuously driven shaft upon which said cam is mounted, a timing shaft, a bevel wheel on said cam shaft, a worm wheel on said timing shaft, a.

Worm upon a countershaft gearing with said worm wheel, a bevel wheel on said countershaft gearing with the bevel wheel on said cam shaft and timing cam carried by vsaid timing sli ift, substantially as specified.

3. An air filter comprising a dust4 collecting hopper and a conveyer for removing the collected dust from said hopper, a filter chamber mounted upon said hopper, filter bags suspended in said chamber, means for suspending said filter bags and normally maintaining them in tension, a suction chamber communicating with said filter chamber, a valve located in said suction chamber, a rod for operating said valvel to open said filter chamber to suction and at mosphere alternately, means for sliding said valve operating rod bodily in one direction, a spring for sliding the said. rod inthe other direction, a shaking trigger, means for operating said trigger to intermittently collapse the filter bags against the infiuence of .the tensioning spring, a cam controlling the operations of said trigger, and timing cams for controlling the timing of the shaking and valve operating mechanism, substantially as described.

4. An airufilter comprising a dust collecting hopper, a filtering chamber mounted upon said hopper, an inlet pipe for the admission of dust laden air into said chamber, a conveyer for removing the collected dust from' said hopper, iilter bags suspended in said chamber, a spider from the arms of which said lter bags are suspended, springs operating normally to maintain said bags in tension, a suction chamber communicat; ing with s aid filter chamber, a valve for alternately opening said filter chamber to suction and atmosphere, a link connected at one end to the valve, a 'bell crank lever, one arm of which is connected to the valve -operating rod and the other end to said link, means for causing said valve operating rod to slide bodily to operate said valve, a shaking trigger and means for momentarily operating said shaking triggerl to collapse-the l filter bags against the inHuence of vthe Y springs and timing cams for timing said op erations, substantially as specified. In testimony whereof I afiix my signature in presence of two witnesses.

' FREDERICK WILLIAM ROGERS WILLIAMS. Witnesses:

` J No-: T. MOULD,

LEONARD M. ORANGE.

etA 

